Plants have a family tree stretching back nearly half a billion years.
They have developed an extraordinary range of strategies to survive.
This tree is a bristlecone pine.
It's taken thousands of years to reach this size.
It has seen empires rise and fall,
kings, queens and presidents come and go
and may have seen the sun rise more than 1.5 million times.
Bristlecone pines are the oldest living things on Earth.
Bamboo is the fastest growing plant.
It will be full-grown - 30 metres tall - in just 90 days.
Like animals, plants are constantly competing for food.
Striving to produce offspring
and battling against predators.
They will deceive and, in some cases,
they will even hunt.
We often don't notice such dramatic behaviour because, to our eyes, it happens so slowly.
But if time is compressed
and you shift perspective to the plants' point of view,
their world comes spectacularly to life.
The events in this woodland
can build to a view of half a year in less than a minute.
Like animals, plants need food and water.
But what sets them apart is their struggle for light.
Plants must have light in order to grow and will do anything to get as much as they need.
The forest might appear to be the perfect place for plants to thrive.
Yet down here on the forest floor
is one of the hardest places imaginable
for a young plant to begin its life.
The canopy above is so thick
that only a little sunlight can filter through.
For this sapling, too little light means death.
But plants on the forest floor need not be passive.
If the light won't come to them,
they can go to the light.
But they still have a problem.
The light is 50 metres above them.
So, they must climb.
It's much easier to use another plant as scaffolding.
But they won't get very high unless they can hold on tight.
Like fingertips searching for a hold,
this ivy's adhesive pads grip the bark.
Instead of sticking to the trees, some climbers use sharp claws.
The cat's claw creeper hooks its tendrils into the tiniest crevices
and hauls itself to the top.
With every metre it climbs,
the light gets a little stronger, fuelling more growth.
This tendril of a passion flower seems to flail aimlessly in mid-air,
but in fact it's searching for an anchor point.
Its tendril coils on itself, pulling the plant towards its support.
In a matter of just days, these climbers make it to the canopy.
Now with light in plentiful supply, these plants are able to flower.
Other plants have a different strategy
to find the light they need in the crowded forest.
These are air-plants.
They grow on the upper branches of tall trees
and spend their whole lives basking in the light.
But growing 50 metres above the ground does have its drawbacks.
Most plants get water and nutrients through their roots in the ground.
For an air-plant, with their roots planted in the tree tops,
this isn't an option.
But they have a solution.
First, the bare roots have an extraordinary ability to soak up water like blotting paper.
The slightest rain or mist, and they absorb every drop.
They also have a way of gathering nutrients.
Their roots trap falling leaves which eventually rot
and provide the plants with their own personal supply of compost.
20,000 different plants -
orchids, bromeliads and ferns have taken up this remarkable lifestyle.
For a plant to thrive, it must not only get enough nutrients,
but also the right balance of nutrients.
The soil in this waterlogged bog is very poor quality, lacking in nitrogen.
But these strange plants have an ingenious strategy.
Their leaves are covered in tentacles, tipped with droplets of what appears to be morning dew.
These droplets give the plant its name - the sundew.
They're sweet-smelling and attractive to many insects.
But they're also extremely sticky.
Mosquitoes emerge in huge numbers from the boggy water
and the sundews are ready.
The sundew's tentacles are living fly-paper.
Struggling only makes matters worse.
With each contact, the plant tightens its grip.
As more and more tentacles envelop the prey,
the droplets spread across its body.
Eventually, the insect is smothered and drowns in sticky fluid.
Digestive enzymes break down the body into a nitrogen-rich meal
which is absorbed by the plant.
Without animal tissues, this plant would not survive.
But there's another carnivorous plant
that's an even more sophisticated predator.
The Venus fly trap.
Like the sundew, it makes itself very attractive,
oozing nectar across the brim of each leaf.
But any visiting insect had better watch out for these six tiny hairs.
This fly has to tread carefully.
If it strikes one hair,
it can carry on feeding.
But a timer has been set.
A second strike in less than 20 seconds and the fly is doomed.
An electrical impulse is triggered and the leaf snaps shut in just a fraction of a second.
The tips lock together like prison bars.
If the fly is very big, or very small, it may just manage to escape.
But most are trapped.
And die.
Ten days later, the trap re-opens.
All that remains is a husk.
The plant has finished its meal and resets itself for its next victim.
But there is one time of year when the Venus fly trap
needs some of the visiting insects to live.
It needs their help to be pollinated.
It sends up flowers on tall stems,
well away from the danger of the traps below.
Here, insects can feed safely on nectar.
In return, they provide a vital service,
carrying pollen from flower to flower.
But the truce is only temporary.
When pollination is over, it's back to business as usual.
80% of plant species on Earth have flowers.
Flowers have just one role -
to enable the plant to produce offspring.
Colour, perfume, nectar and shape
all act to make a flower irresistible.
Sunflowers grow to face the rising sun.
The warmth of the rays speeds the production of nectar
and this lures pollinators.
One after another,
hundreds of individual florets produce pollen-covered stamens.
And, like most flowers,
sunflowers establish a close relationship with animals
in order to ensure their reproduction.
As these bees busily feed on nectar,
they unwittingly brush against the stamens, collecting pollen,
and then carry it from flower to flower.
The sunflower is fertilised.
In the sun-drenched fields of southern France,
the flowering season is a long one,
but not all plants have this luxury.
Cradle Mountain in Tasmania is blasted by bitter Antarctic winds.
To reproduce, the Richea honey bush must flower.
But the delicate parts of the flowers risk being damaged by the cold.
The plant appears to have an ingenious solution.
The flower petals fuse together,
forming an insulated, protective case around its stamens.
However, this creates another problem,
the flower case is so well sealed that, unfortunately,
it also keeps out pollinating insects.
During brief, sunny spells,
the flowers warm up and suddenly start producing nectar.
This attracts a bird - the Black Currawong.
It has the strength to rip open the flowers' outer casing
and gets its reward of nectar.
At the same time, it exposes the delicate stamens to waiting insects.
With luck, there's enough time for pollination
before the biting wind kills the flowers.
For some plants, the relationship with their pollinators
is not collaborative,
it's war.
Butterflies, and in such numbers,
would seem to be perfect pollinators for any flower.
The Sandhill milkweed blooms every spring
in the sandy meadows of Florida.
It times its flowering perfectly to match the arrival
of Monarch butterflies migrating here from Mexico.
The Monarchs search out milkweed plants,
but they have something other than pollination on their minds.
Rather than collect pollen,
this female lays her eggs on the milkweed leaf.
This is the only plant the caterpillars can eat.
But the milkweed has a defence mechanism.
As the caterpillar bites into a vein,
a kind of latex swells out engulfing it.
If the caterpillar isn't quick, it will drown...
or find its jaws glued together.
The plants' defence is so effective
that only one third of the Monarch caterpillars
make it through the first day.
But the caterpillars that survive, grow in size and strength.
And they go for the jugular.
By carefully chewing through the main vein,
the caterpillar drains the leaf of latex
and cuts off its supply.
The milkweed's leaf is now defenceless
and the caterpillar eats in safety
before preparing to pupate into a butterfly.
But after about ten days,
it becomes clear why the plant has endured this onslaught.
A newly-hatched Monarch simply can't resist the nectar-filled cups
of the milkweed flowers.
As it moves across the flower heads,
its feet slide between grooves in the petals
where the flower's pollen sacs are waiting.
As it flies off, the Monarch's feet hook out the pollen
and carry it to the next flower and pollination is achieved.
Although the milkweed has paid a heavy price,
in the end it used the Monarch to get its way.
Here in Dominica there's a plant that is so manipulative
that it has enslaved its pollinator.
The bright red structures of the Heliconia are actually modified leaves.
These are its flowers.
They may be small, but they play a very important role
keeping nectar well guarded at the very bottom of their long stems.
The purple-throated Carib hummingbird,
with its long curved beak,
is the only bird capable of reaching this energy-rich food.
But, cleverly, the Heliconia rations the amount of nectar it produces
to force the hummingbird into returning to the flower
time and time again.
Every time it makes a visit,
it picks up more pollen on its beak and feathers.
The hummingbird is like an addict.
Not only does it never stray,
but it will aggressively defend the flowers from thieves.
The plant is the master in this relationship.
To ensure it gets pollinated,
Heliconia has made the hummingbird its prisoner.
A plant's problems don't end once it's been pollinated.
Plants need to spread their seeds as far away as possible,
otherwise the adults will be in direct competition with their offspring.
Here in South Africa, one flower achieves this
by performing a remarkable trick.
The plant waits dormant underground for more than a year.
The first heavy rains for many months
are the trigger the plant has been waiting for.
Brunsvigia burst into flower.
Their timing is perfect.
These conditions are ideal for insects too.
The flowers enjoy a few days of frenzied pollination.
But it's not long before the searing heat returns.
The flowers start to wilt, shrivel and die.
Brunsvigia now needs to disperse its seeds widely,
yet the flowers still have their seeds trapped inside.
But the flower isn't finished yet.
There are strong winds that blow across this landscape.
They snap the dry, dead stalks, sending each and every plant
cart-wheeling across the ground, casting seeds as it goes.
With the heat threatening to dry them out,
the seeds' germination has to be immediate.
Deep in the forests of Borneo,
some plants also use the wind to disperse their seeds,
but in a completely different way - by giving their seeds wings.
Some are helicopters that twist and turn their way down to the ground.
But there is one that has a design
that enables it to travel greater distances than all the others.
This is Alsomitra.
Its football-sized pod
is packed full of hundreds of extraordinary seeds.
Each is an almost aerodynamically perfect glider
that can be supported by even the slightest breeze.
Its paper-thin upswept wings
allow it to travel hundreds of metres through the forest.
Once the seed hits the ground,
the wings rot away and the seed starts to germinate.
A new Alsomitra vine starts to grow up towards the canopy
and into the light - well away from its parent.
There are other ways to disperse seeds
and plants have evolved different tactics
depending on where they live.
In the desert of Arizona lives a master - the Saguaro cactus.
In the cool of the night, the cacti open their radiant flowers.
They're soon visited by nectar-feeding bats
and as the bats move from cactus to cactus,
they pollinate them.
Each flower only lasts a night,
but over three weeks, each cactus will produce more than 200 flowers.
Every pollinated flower immediately begins to form a fruit at its base,
packed with thousands of seeds.
The mature Saguaro cacti are superbly adapted
to survive out in the intense heat of the Sonoran Desert.
But their seeds are delicate, and must find shade or they will scorch to death before they germinate.
The seeds are covered with succulent sweet flesh -
a meal that all sorts of desert creatures find irresistible.
White winged doves are among the first to reach the ripening fruit.
The seeds survive in the birds' stomachs
and will be carried many miles
before being deposited in their droppings.
Their own little packet of fertiliser.
But the cactus doesn't just rely on birds.
Fallen fruit provides a bonanza for creatures on the ground.
Foraging ants quickly gather seeds and flesh.
That's if a tortoise doesn't get there first.
The greater range of animals the cactus can get to eat its fruit,
the more likely the seeds within will be carried to the perfect place to germinate.
The ants carry the seeds underground into their nests,
often excavated among the roots of trees.
The tortoise too will head for shade.
It spends much of its day cooling off under trees
where it's sure to leave undigested seeds in its dung.
Now the seeds wait for the rains to come.
THUNDER
Of the 40 million or so seeds a cactus produces in its lifetime,
the chances are that only one will develop into a plant
that outlives its parent.
If it was lucky enough to find shade,
a seed will still take ten years
to become a five centimetre tall cactus.
To reach the size of its parents, possibly ten metres,
will take at least 100 years.
Plants can survive in the most unlikely and inhospitable places on Earth.
Here on Socotra, a remote island in the Arabian Sea,
the dry season is brutal.
But this strange tree has a strategy to survive it.
The Dragon's Blood tree.
The key to their success lies in their bizarre shape.
They live on the mountain tops where there's little soil,
but there are critical compensations.
Occasional morning mists sweep across the high ground.
The mist condenses on the skyward-pointing waxy leaves.
The droplets run down to the centre of the trunk and down to its roots.
Water is so precious that the tree cannot afford to waste any.
Drops that do escape and fall to the ground are not totally lost.
The tree's huge, densely packed crown acts as a parasol.
It shades the ground so effectively it allows time for the water to seep into the sand.
And it also shades the network of roots
that lie just under the surface.
Another plant shares this parched desert,
but survives in a very different way.
The Desert Rose.
In really harsh conditions,
it jettisons its leaves to minimise water loss.
Strangely, it chooses this time to flower.
Its bulbous trunk is like a barrel that stores water all year round.
It's so hardy it can grow out of bare rock.
It might seem that conditions can't get much tougher
for a plant than here.
But, for some, the conditions are even harsher.
Six hours ago, here on the coast of Australia,
this tree was high and dry on a sandy beach.
For almost all plants, saltwater is lethal,
so submersion of this tree's roots by the tide twice a day
should kill it.
Yet this Red Mangrove is flourishing.
The retreating tide reveals the key to surviving the sea's assault.
The mangrove's roots are covered in warty growths.
The growths surround pores that take in oxygen from the air
when the roots are above water.
But the pores become useful in a quite different way when they're submerged again.
They allow water into the plant,
but filter out 99% of the salt as it passes through.
Any salt that gets in is pumped into a few sacrificial leaves that turn yellow and are discarded.
Plants can not only cope with being poisoned, parched and scorched,
but they can also survive being frozen.
In the world's northern forests,
the changing of the seasons creates its own challenges.
As summer moves to autumn,
plants prepare themselves for the toughest time of their year.
Broad-leaved trees unveil what seems to us a colourful spectacle.
But for these plants it is the beginning of a series of urgent and drastic survival strategies
to cope with the coming cold.
They begin by pulling all the water and nutrients within their leaves back into the trunk.
The last rays of useful sunlight are channelled
into making a sugary anti-freeze
that will protect the body of the tree.
The green pigment - chlorophyll -
disappears, leaving purples, reds, oranges and yellows.
Finally, the leaves die and the trees discard them.
As temperatures drop below freezing,
the plants of broad-leaved forests settle down
to hibernate until spring.
Pine trees can survive much colder conditions.
They have anti-freeze in the leaves themselves,
that means they can keep them all winter.
The needle-like leaves also have a thick waxy coating
that limits any water loss through pores.
The winters here are long and hard.
The trees have to survive temperatures of down to -40C for five months.
But one pine tree is capable of surviving even harsher conditions.
These pines live at the limit of life -
above 3,000 metres in the mountains of western America.
Almost continuous freezing temperatures and savage winds
make life so tough that these bristle cones
only manage to grow for six weeks of the year.
Everything is about conserving energy.
They hardly ever shed their needles, which can last more than 30 years.
After centuries of being blasted by storms,
a full-grown tree still survives
with only a strip of bark a few inches wide.
These trees live life at such a slow pace that they can reach great age.
Some are over 5,000 years old.
It's been said of the bristlecones,
that to live here is to take a very long time to die.
As the northern spring approaches,
the warming temperatures and increased day length
release the land from winter.
Plants that have lain dormant begin to grow again.
These have over-wintered,
buried in the mud at the bottom of this frozen lake.
The retreating ice allows the water to warm
and this white water lily to flourish for another season.
And, as all the trees come out of their winter rest,
the vivid green of new leaves returns to the land.
From the frozen north to the southern deserts,
the spring bloom symbolises the success of plants
in surviving against the odds.
But the most successful type of flowering plant
is one that makes up 20% of all plant life on the planet.
Grass.
There are 10,000 different species.
Today, they form the diet of many thousands of different animals.
And a few grasses, particularly rich in nutrients,
have developed a relationship with one animal
and together, the two have changed the world.
10,000 years ago, we humans started to cultivate rice
in order to harvest its food-rich seeds.
Now, half of the world's population depends on it.
But there is one other grass that has spread
even further across the planet
due to its relationship with humans...
wheat.
It underpinned the development of western civilisation.
Today, it covers more of the land than any other kind of plant.
Plants have been residents on land longer than animals
and have had nearly half a billion years to evolve.
During that time, they've diversified into countless forms
and have colonised every habitat.
As well as collaborating with animals,
plants are sometimes their masters,
exploiting them to their own advantage.
Plants capture energy from the sun
and all life on land, directly or indirectly, depends on them.
So, ultimately, plants fuel the diversity of life on Earth.
To see the behaviour of plants as they struggle to survive
presented a unique challenge.
The plants team had to employ many techniques,
including time-lapse and high-speed photography.
They filmed in jungles, deserts, swamps and plains,
but they also spent many hours shooting in a converted barn
just outside Exeter.
All under the watchful eye
of green-fingered cameraman, Tim Shepherd.
Filming plants in time-lapse takes so long
and is so susceptible to changes in light levels and weather conditions
that some key sequences had to be filmed in this studio.
In time-lapse, a camera takes a series of pictures
over an extended period of time,
so, when played back, the action appears speeded up.
These sunflowers actually take three days to open,
but are seen opening in a matter of seconds.
The most complex time-lapse the team attempted
showed an entire growing season
in an English woodland in one continuous shot.
A shot that took two years to create.
I think this is going to be the spot.
As the producer, Neil Lucas
leads Tim and Mick Connaire, the graphic designer,
out to the location,
he explains his idea.
Well, this is one that I thought... That's a lovely rock. Just here.
And I think that'd be great to have the brambles growing along.
It will be a tracking shot through the wood with plants growing,
flowers blooming and the woodland coming to life
over the course of a year.
We're condensing one year down into less than a minute.
We have to have them all coming out at the same time, multiple passes.
How long does a foxglove take to grow?
Well, if we start just before the buds are about to open
and you've got the whole long spike,
then top to bottom that's probably about three weeks.
So, even if you wanted to, you couldn't shoot the plants here
because, three weeks, the weather's going to change,
you've got the day-night and also just leaving the equipment here running, it's not feasible, is it?
You just have to imagine the changes that would happen here in three weeks
and if that was all joined together
and one frame the plant might be there
and you take a shot of it an hour later and, if the wind's blowing,
it's over here somewhere and then you join those two shots together...
It just won't work. So what we've got to do is not only have we got to produce a move
that is exactly the same repeatable move,
a track that can be built exactly the same again in a studio.
Build exact models of every object in here
so we can put plants in the right places and then time everything,
so they grow just as the camera happens to be pointing at them. Yes. OK.
The scale of the challenge is dawning on them.
Months of planning lie ahead.
The following spring, the team head back to the wood.
With no road access,
manpower is the only way to get the tonnes of equipment into position.
Everyone's wondering how this will turn out, including the locals.
Go up about an inch. Straight now.
Start like that.
Position now is 221556.
We've done it wrong.
That's pulled it. Hang on - that's pulled it terribly.
BLEEP!
Did that snap? No, it's pulled this wheel round.
Two days of building, levelling, test runs
and even a few minor disasters
and finally the track is ready to run.
OK, that's pretty close.
If you move your... Can you see that little bit of lichen? Go to 8,900.
Accuracy is paramount.
Yeah, whatever we shoot in the studio,
it's got to match this landscape exactly,
so unless we know precisely where everything is
relative to the camera,
there's no way of placing the plants in the studio in the right place.
So we have to measure the hell out of it.
Oh, bloody hell, it's spot on. Look at that.
So 250. OK.
Shot by shot and step by step,
the camera inches its way back up the 30 metre track.
Well, that's working.
This is only the background shot.
There is still a huge amount of other filming to be done.
The track has to be rebuilt exactly as it is on location
back in the studio - a task that will take weeks to get right.
Right in front of the tree at the end of the rock.
Using the detailed measurements taken in the wood,
the position size and shape of every structure
has to be matched precisely.
35. 35, yeah.
The slightest discrepancy will put the team back to square one.
Chicken-wire and polystyrene form the rocks and trees of the woodland.
Blue screen is used to cover every inch of the set
to allow the original shot to be mapped on later in graphics.
Once built, and with the plants placed in their exact locations,
filming can start.
The stars of the show finally make an appearance.
Timing is everything.
With each plant taking up to three weeks to flower
there's only one chance of getting it right.
A year later and thankfully so far all had gone to plan.
The final stage is to bring all the pieces together seamlessly -
a challenging task for any graphic designer.
We've got things overlapping that wouldn't necessarily grow at the same time,
but all the growth of each individual plant is absolutely accurate.
It's exactly what they would do.
We're just seeing it in a shorter space of time.
That big rock in the foreground at the end of the shot that we wanted to try and get stuff climbing on,
that's worked really, really well.
This is the bramble here.
Had to measure it so carefully so we knew exactly where these things were, how round they were,
how deep they were from the camera.
Then when we take the blue out of that
you can see that the plants start to sit into the shot
exactly where we wanted them to be,
things appearing from behind the tree,
forming on the top of the rock.
That's fantastic. So here they go.
If I switch those off
you can see how just how neatly they slot into the shot.
If we play it, you can see
that everything's sticking in pretty well.
96 layers, 15 tracks and two years later, the shot is finally complete.
A 60-second shot that proved to be one of the most complex
ever attempted in natural history film-making.
Subtitles by Red Bee Media Ltd
E-mail subtitling@bbc.co.uk